Dandruff is a common scalp condition that that causes flaky skin and an itchy scalp.
What Are the Signs & Symptoms of Dandruff?
Common signs and symptoms of dandruff include:
white flakes of dead skin in your hair and on your shoulders
red, crusty, or raw areas on your scalp
an itchy scalp
What Causes Dandruff?
Dandruff is a mild form of seborrheic dermatitis. The exact cause of seborrheic dermatitis is not known, but it's likely a combination of things like:
too much skin oil (sebum) in the oil glands and hair follicles
a type of yeast found on the skin called Malassezia
Stress, cold and dry winter weather, and some hair care products may make dandruff worse.
Almost anyone can have dandruff. Many teens and adults live with it. Hormone levels are high during teen years, which causes more oil production. This may be why dandruff usually begins around puberty.
Dandruff isn't contagious. You can't catch it from or give it to another person.
How Is Dandruff Diagnosed?
Health care providers can diagnose dandruff and seborrheic dermatitis based on symptoms (like an itchy scalp and flakes on the shoulders) and an exam.
How Is Dandruff Treated?
In most cases, over-the-counter dandruff shampoo can control a person's dandruff. Check the labels for these common "active ingredients":
selenium sulfide 1% shampoo (such as Selsun Blue®, or a store brand)
zinc pyrithione shampoo (such as Head & Shoulders®, Zincon®, DHS zinc®, or a store brand)
tar-based shampoo (such as T-Gel®, DHS tar®, Pentrax®, or a store brand). Tar-based shampoos can make the scalp more sensitive to sunlight, so users should wear a hat outside. Don't use a tar shampoo on dyed or treated hair. Long-term use can stain skin, hair, and nails.
ketoconazole shampoo (such as Nizoral 1%® or a store brand)
Follow the label directions on how much to use and how often. When your dandruff improves, it's OK to use dandruff shampoo less often. Once a week might be enough to keep flakes off your shoulders.
If dandruff doesn't get better after 4–6 weeks, try another shampoo with a different active ingredient.
Talk to the pharmacist if you have any questions about dandruff shampoos.
When Should I Call the Doctor?
Call your health care provider if:
Your dandruff doesn't go away with dandruff shampoo.
Dandruff or itching gets worse.
Your scalp gets red or swollen.
You have red and flaky skin in areas other than your scalp.
The doctor may prescribe prescription-strength shampoos or topical steroids for itching and redness.
What Else Should I Know?
People with dandruff also may get seborrheic dermatitis on other parts of their body, including: